Image

Sign upLogin

Settings

Change Password

Logout

Link Function

This documentation is valid for:
GeneXus 18 Help
GeneXus 17 Help

Returns a character string with a URL format.

Syntax

Link(Object | URL [ , Par₁ , ... Par_n] )

Where:

Object | URL
Is a Transaction, Web Panel, Web Component, Panel, Work with, Image, or URL to link.

[ par₁ ] ... [ par_n ]
The set of parameters to pass to the object or URL.

Type Returned:
Character

Scope

Objects: Procedure, Transaction, Web Panel, Panel, Data Provider
Generators: .NET Framework, .NET, Java, Apple, Android, Angular

Description

This function returns a string to be used later in different scenarios (typically to add a link to a UI Control, or invoke an internal or external resource).

Samples

Linking Web Objects

Use case 1: Add a link (known Web Object) to a UI Control

&MyLink = Link(MyObject,&Parm1, &Parm2)
Textblock1.Link = &MyLink

&MyObject = 'Module1.MyObject'
&MyLink = Link(&MyObject,&Parm1, &Parm2)
Textblock1.Link = &MyLink

MyObject can be a Web Panel object, Transaction object, Web Component object (with URL access property set to Yes), Image object.

Use case 2: Instantiate a Web Component control with a Web Component object

&MyLink = Link(MyObject,&Parm1, &Parm2)
WebComponent.Object = CreateFromURL(&MyLink)

&MyObject = 'Module1.MyObject'
&MyLink = Link(&MyObject,&Parm1, &Parm2)
WebComponent.Object = CreateFromURL(&MyLink)

MyObject can be a Web Component object.

Use case 3: Create a link from a Web Object and invoke it

&MyLink = Link(MyObject,&Parm1, &Parm2)
Link(&MyLink) //The link command is used to invoke the link, without returning any values.

&MyObject = 'Module1.MyObject'
&MyLink = Link(&MyObject,&Parm1, &Parm2)
Link(&MyLink) //The link command is used to invoke the link, without returning any values.

MyObject can be a Web Panel object, Transaction object, Web Component object (with URL access property set to Yes).

Linking Panels

Use case 4: Create a link from a known Object and invoke it

&MyLink = Link(MyObject,&Parm1, &Parm2)
call(&MyLink)

&MyObject = 'Module1.MyObject' 
&MyLink = Link(&MyObject,&Parm1, &Parm2) 
call(&MyLink)

MyObject can be a Panel object, Work With pattern and Work With object.

Note about use cases 1 to 4: Recommended Coding style: Write 'MyObject.Link(Parm1,Parm2)' instead of Link(MyObject,Parm1, Parm2) when the linked object is known at design time.

Linking external resources

Use case 5: Link resources of the same site

You can use the link function to get a link to an external resource of the same site.

5.1: Document-relative

&MyLink = Link(!'mypath/document',&Parm1, &Parm2)

Compatibility note specific to Java generator: If the linked URL is a file (e.g. 'mypath/myspreadsheet.xlsx'), the resulting string is server-relative.

5.2: Server-relative

&MyLink = Link(!'/mypath/document',&Parm1, &Parm2)

Use case 6: Link resources of another site

6.1: Protocol-relative

&MyLink = Link(!'//example.com:80/mypath/folder1',&Parm1, &Parm2)

6.2: Absolute

&MyLink1 = Link(!'https://example.c:80/mypath/document',&Parm1, &Parm2) 
&MyLink2 = Link(!'http://user:pwd@example.com:80/mypath/document',&Parm1, &Parm2)
&MyLink3 = Link(!'myscheme://example.com:80/mypath/document',&Parm1, &Parm2)

Considerations

If the URL to be linked is stored in an attribute, you can write:

for each Company
   &MyLink = link(att:CompanyURL)
   //do something with &MyLink
endfor

Rewrite rules: When there are rewrite rules in the KB (i.e., at least one URL Rewrite object), all URLs are handled at runtime as server-relative URLs because it is required to avoid potential URL ambiguity. Therefore, in that case, the link function applied to a relative URL always returns a server-relative URL.
Parameter style: The Parameters Style property for Environments determines how URLs are built when they have parameters. Thus, the link function result also takes into account this property.